What would be the best style to warmness my garage?
Answers: Any boiler that uses an open flame would entail to be vented, or you could hold a problem with the carbon monoxide buildup. An unscrew flame source can be a problem with some projects you might want to do surrounded by the garage too, hehehe.
An electric 'oil filled' radiator type stove would probably do nicely... its not 'instant' grill.... you'd want to turn it on a little while beforehand needing to travel out to work in the garage. I use a DeLonghi model myself, surrounded by a porch that was converted to an department. Its got window all the road around, but that little heater does a great undertaking of keeping it comfortable.
You should think roughly speaking adding insulaton to that remaining wall space... you can purchase it surrounded by battens, and do it yourself. Sheet styrofoam (blueboard, etc) can also be glue to the inside of the garage door, to help insulate it. (The type of insulation found below vinyl siding is usually about 1/4" tacky... you can get it up 2" gluey at most building supply stores, though, you wouldnt necessarily want more than 3/4" on a garage door.
Every little bit helps.
Have Fun
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